// 远程进程管理：进程列表 / 结束进程。
// gopsutil 跨平台实现，与 file/shell 同为被控 HTTP 能力——BS 与客户机被控端共用，
// 经 zonat 隧道 + web-gateway 反代出网（typ=process，页面 www/process.html）。

package process

import (
	"encoding/json"
	"net/http"
	"os/exec"
	"runtime"
	"sort"
	"strconv"

	"github.com/shirou/gopsutil/v3/process"

	"git.zeroonesoft.cn/golib/remote-core/webhttp"
)

// ProcItem 进程列表行。
type ProcItem struct {
	Pid        int32   `json:"pid"`
	Name       string  `json:"name"`
	Status     string  `json:"status"`
	User       string  `json:"user"`
	CPUPercent float64 `json:"cpuPercent"` // 进程存活期累计 CPU 占用率(gopsutil 口径)
	MemRSS     uint64  `json:"memBytes"`   // 物理内存占用(字节)
	MemPercent float32 `json:"memPercent"`
	CreateTime int64   `json:"createTime"` // 启动时间(Unix 毫秒)
	Exe        string  `json:"exe"`
	Cmdline    string  `json:"cmdline"`
}

// RegisterRoutersProcess 装配进程管理路由: GET /process/list, POST /process/kill。
func RegisterRoutersProcess(r webhttp.Router) {
	r.GET("/process/list", listProcesses)
	r.POST("/process/kill", killProcess)
}

func fail(w http.ResponseWriter, msg string) {
	webhttp.WriteJSON(w, http.StatusOK, map[string]any{"code": 1, "msg": msg, "data": nil})
}

// listProcesses 全量进程列表(按内存占用降序)。
func listProcesses(w http.ResponseWriter, _ *http.Request) {
	procs, err := process.Processes()
	if err != nil {
		fail(w, "枚举进程失败: "+err.Error())
		return
	}
	items := make([]ProcItem, 0, len(procs))
	for _, p := range procs {
		item := ProcItem{Pid: p.Pid}
		if name, e := p.Name(); e == nil {
			item.Name = name
		}
		if st, e := p.Status(); e == nil && len(st) > 0 {
			item.Status = st[0]
		}
		if u, e := p.Username(); e == nil {
			item.User = u
		}
		if cpu, e := p.CPUPercent(); e == nil {
			item.CPUPercent = cpu
		}
		if mem, e := p.MemoryInfo(); e == nil {
			item.MemRSS = mem.RSS
		}
		if mp, e := p.MemoryPercent(); e == nil {
			item.MemPercent = mp
		}
		if ct, e := p.CreateTime(); e == nil {
			item.CreateTime = ct
		}
		if exe, e := p.Exe(); e == nil {
			item.Exe = exe
		}
		if cmd, e := p.Cmdline(); e == nil {
			item.Cmdline = cmd
		}
		items = append(items, item)
	}
	sort.Slice(items, func(i, j int) bool { return items[i].MemPercent > items[j].MemPercent })
	webhttp.WriteJSON(w, http.StatusOK, map[string]any{"code": 0, "msg": "OK", "data": map[string]any{"list": items}})
}

// killProcess 结束进程: {pid: 必填, name: 可选校验(防 pid 复用误杀)}。
// Windows 上 gopsutil 权限不足时回退 taskkill /F /T(连子进程树强杀)。
func killProcess(w http.ResponseWriter, r *http.Request) {
	var req struct {
		Pid  int32  `json:"pid"`
		Name string `json:"name"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil || req.Pid <= 0 {
		fail(w, "参数错误: pid 必填且为正整数")
		return
	}
	p, err := process.NewProcess(req.Pid)
	if err != nil {
		fail(w, "进程不存在: "+err.Error())
		return
	}
	if req.Name != "" {
		if name, e := p.Name(); e == nil && name != "" && name != req.Name {
			fail(w, "进程名不匹配(实际 "+name+"), 已拒绝结束")
			return
		}
	}
	if err := p.Kill(); err != nil {
		if runtime.GOOS != "windows" {
			fail(w, "结束进程失败: "+err.Error())
			return
		}
		if out, e := exec.Command("taskkill", "/F", "/T", "/PID", strconv.Itoa(int(req.Pid))).CombinedOutput(); e != nil {
			fail(w, "结束进程失败: "+err.Error()+"; taskkill: "+string(out))
			return
		}
	}
	webhttp.WriteJSON(w, http.StatusOK, map[string]any{"code": 0, "msg": "OK", "data": map[string]any{"pid": req.Pid}})
}